The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 27, 1999
Filed:
Sep. 05, 1997
Hitachi, Ltd., , JP;
Abstract
A regulator for an alternator installed in a vehicle has a switching circuit in which a field current limiting transistor interruptibly controls a flow of current to a field coil of the alternator. A battery output voltage detection terminal is connected to the battery, and an alternator output voltage terminal is connected to the alternator. A diode connected to the battery output voltage detection terminal has a reverse recovery time of 20 ns-20 .mu.s, and a resistor is connected between the diode and the alternator output voltage terminal. A control circuit controls the switching circuit, in order to regulate the voltage at a connection point of the diode and the resistor so as to keep the voltage constant, and an alarm generating circuit illuminates a charge indicator lamp if the voltage at a junction of said diode and said resistor exceeds a reference voltage.